Home / 1,243.36-1,864.40-421.34

Finding the Fourth Proportional to 1,243.36, 1,864.40 and 421.34

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Solution

The fourth proportional to 1,243.36, 1,864.40 and 421.34 is: 631.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,243.36 : 1,864.40 = 421.34 : x
  2. Step 2: Convert to fraction form
    1,243.36/1,864.40 = 421.34/x
  3. Step 3: Cross multiply
    1,243.36x = 1,864.40 × 421.34
  4. Step 4: Simplify right side
    1,243.36x = 785,546.30
  5. Step 5: Solve for x
    x = 785,546.30/1,243.36
  6. Step 6: Final answer
    x = 631.79

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.